Which hormones promote the flowering in long day plants and also control sex expression in certain species?

Options

(a) ethylene
(b) gibberellin
(c) cytokinins
(d) auxin

Correct Answer:

gibberellin

Explanation:

Gibberelins are growth promoting phytohormones. Some of plant species flower only if the light period exceeds a critical length, and others flower only if this period is shorter than some critical length. Gibberelins can substitute for the long-day requirement in some species, showing an interaction with light. Gibberelins also promote the formation of male flowers on genetically female plants, e.g., Cannabis. They also replace female flowers with ,male flowers on monoecious plants of cucurbits.